Littérature scientifique sur le sujet « Endogenous oscillators »
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Articles de revues sur le sujet "Endogenous oscillators"
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Grechenko, T. N., A. N. Kharitonov et A. V. Zhegallo. « Evolutionary paths of electric oscillators ». Experimental Psychology (Russia) 8, no 2 (2015) : 105–18. http://dx.doi.org/10.17759/exppsy.2015080208.
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The endogenous electrical signals play an important role in information processes occurring in living systems. They are found in living beings of different evolutionary levels from prokaryotes to multicellular eukaryotes. We hypothesized that the presence and variety of endogenous oscillators in individual organisms are connected with the way they survive, i.e. totally dependent on the community or partially independent of it. To test the hypothesis, we recorded electrical activity from individual cells and their communities in experiments with the earliest evolutionary beings, prokaryotes: cyanobacteria Oscillatoria terebriformis, Geitlerinema sp. and Halothece sp., the unicellular eukaryotes: yeast Saccharomyces cerevisiae and ciliates Paramecium caudatum, as well as from shellfish Helix pomatia and H. lucorum. The experimental results suggest that the variety of oscillators in the individual, the properties and functions that they perform, may provide a key to understanding the individual/social organization of living systems.
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Oprisan, Sorinel A. « All Phase Resetting Curves Are Bimodal, but Some Are More Bimodal Than Others ». ISRN Computational Biology 2013 (12 décembre 2013) : 1–11. http://dx.doi.org/10.1155/2013/230571.
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Phase resetting curves (PRCs) are phenomenological and quantitative tools that tabulate the transient changes in the firing period of endogenous neural oscillators as a result of external stimuli, for example, presynaptic inputs. A brief current perturbation can produce either a delay (positive phase resetting) or an advance (negative phase resetting) of the subsequent spike, depending on the timing of the stimulus. We showed that any planar neural oscillator has two remarkable points, which we called neutral points, where brief current perturbations produce no phase resetting and where the PRC flips its sign. Since there are only two neutral points, all PRCs of planar neural oscillators are bimodal. The degree of bimodality of a PRC, that is, the ratio between the amplitudes of the delay and advance lobes of a PRC, can be smoothly adjusted when the bifurcation scenario leading to stable oscillatory behavior combines a saddle node of invariant circle (SNIC) and an Andronov-Hopf bifurcation (HB).
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Helfrich, Charlotte, et Wolfgang Engelmann. « Evidences for Circadian Rhythmicity in the per° Mutant of Drosophila melanogaster ». Zeitschrift für Naturforschung C 42, no 11-12 (1 décembre 1987) : 1335–38. http://dx.doi.org/10.1515/znc-1987-11-1231.
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per° Mutants of Drosophila melanogaster which are exposed to light-dark cycles (LD) with different Zeitgeber period (T) have a limited range of entrainment. Entrained flies show a characteristic phase relationship of activity to the LD which depends on the period of the driving cycle as expected by oscillator theory. Both facts are taken as evidence that per° possesses endogenous oscillators and that the per gene product is not concerned with central clock structures but rather might be responsible for the mutual coupling between the individual oscillators in a multioscillatory system controlling locomotor activity.
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Braun, H. A., M. T. Huber, M. Dewald, K. Schäfer et K. Voigt. « Computer Simulations of Neuronal Signal Transduction : The Role of Nonlinear Dynamics and Noise ». International Journal of Bifurcation and Chaos 08, no 05 (mai 1998) : 881–89. http://dx.doi.org/10.1142/s0218127498000681.
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Nonlinear ionic interactions at the nerve cell membrane can account for oscillating membrane potentials and the generation of periodic neuronal impulse activity. In combination with noise, external modulation of the endogenous oscillations allows for continuous transitions between a variety of impulse patterns. Such "noisy oscillators" afford, thereby, an important mechanism of neuronal encoding as is demonstrated here with experimental data from peripheral cold receptors and corresponding computer simulations.
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Isorna, Esther, Nuria de Pedro, Ana I. Valenciano, Ángel L. Alonso-Gómez et María J. Delgado. « Interplay between the endocrine and circadian systems in fishes ». Journal of Endocrinology 232, no 3 (mars 2017) : R141—R159. http://dx.doi.org/10.1530/joe-16-0330.
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The circadian system is responsible for the temporal organisation of physiological functions which, in part, involves daily cycles of hormonal activity. In this review, we analyse the interplay between the circadian and endocrine systems in fishes. We first describe the current model of fish circadian system organisation and the basis of the molecular clockwork that enables different tissues to act as internal pacemakers. This system consists of a net of central and peripherally located oscillators and can be synchronised by the light–darkness and feeding–fasting cycles. We then focus on two central neuroendocrine transducers (melatonin and orexin) and three peripheral hormones (leptin, ghrelin and cortisol), which are involved in the synchronisation of the circadian system in mammals and/or energy status signalling. We review the role of each of these as overt rhythms (i.e. outputs of the circadian system) and, for the first time, as key internal temporal messengers that act as inputs for other endogenous oscillators. Based on acute changes in clock gene expression, we describe the currently accepted model of endogenous oscillator entrainment by the light–darkness cycle and propose a new model for non-photic (endocrine) entrainment, highlighting the importance of the bidirectional cross-talking between the endocrine and circadian systems in fishes. The flexibility of the fish circadian system combined with the absence of a master clock makes these vertebrates a very attractive model for studying communication among oscillators to drive functionally coordinated outputs.
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O'Brien, GM. « Seasonal reproduction in flying foxes, reviewed in the context of other tropical mammals ». Reproduction, Fertility and Development 5, no 5 (1993) : 499. http://dx.doi.org/10.1071/rd9930499.
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Megachiroptera inhabit the Old World tropics and most are seasonal breeders having defined times of testis growth, mating and parturition. In Pteropus scapulatus, the little red flying fox, the robust rhythm of testis cycles is resistant to modification by photoperiod. P. poliocephalus, the greyheaded flying fox, can be manipulated by photoperiod but responds slowly and incompletely. Most mammals live in the tropics, many in seasonally harsh climates, and many breed seasonally. However, few long-lived tropical mammals have been investigated for photoperiodic entrainment of annual reproductive cycles, and only animals from the edge of the tropics have responded. Thus, in long-lived tropical mammals, factors that regulate seasonal breeding have not yet been identified. Endogenous oscillators may generate circannual rhythms centrally. Downstream pathways (reproduction, metabolism, antlers, etc.) may derive their rhythm directly from the oscillator or may be modified by environmental cues. Plasticity of the circannual oscillator resolves confusion from previous contrasts between circannual rhythms and environmentally cued patterns. Plasticity may continue throughout life (species responsive to zeitgebers), but the oscillator may be 'set' in utero in some tropical species. Feedback effects from temperature, nutrition, hormones, etc. can be readily tested in this model of an oscillator generating an endogenous circannual rhythm.
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LoFaro, Thomas, Nancy Kopell, Eve Marder et Scott L. Hooper. « Subharmonic Coordination in Networks of Neurons with Slow Conductances ». Neural Computation 6, no 1 (janvier 1994) : 69–84. http://dx.doi.org/10.1162/neco.1994.6.1.69.
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We study the properties of a network consisting of two model neurons that are coupled by reciprocal inhibition. The study was motivated by data from a pair of cells in the crustacean stomatogastric ganglion. One of the model neurons is an endogenous burster; the other is excitable but not bursting in the absence of phasic input. We show that the presence of a hyperpolarization activated inward current (ih) in the excitable neuron allows these neurons to fire in integer subharmonics, with the excitable cell firing once for every N ≥ 1 bursts of the oscillator. The value of N depends on the amount of hyperpolarizing current injected into the excitable cell as well as the voltage activation curve of ih. For a fast synapse, these parameter changes do not affect the characteristic point in the oscillator cycle at which the excitable cell bursts; for slower synapses, such a relationship is maintained within small windows for each N. The network behavior in the current work contrasts with the activity of a pair of coupled oscillators for which the interaction is through phase differences; in the latter case, subharmonics exist if the uncoupled oscillators have near integral frequency relationships, but the phase relationships of the oscillators in general change significantly with parameters. The mechanism of this paper provides a potential means of coordinating subnetworks acting on different time scales but maintaining fixed relationships between characteristic points of the cycles.
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Bloch, Guy, Erik D. Herzog, Joel D. Levine et William J. Schwartz. « Socially synchronized circadian oscillators ». Proceedings of the Royal Society B : Biological Sciences 280, no 1765 (22 août 2013) : 20130035. http://dx.doi.org/10.1098/rspb.2013.0035.
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Daily rhythms of physiology and behaviour are governed by an endogenous timekeeping mechanism (a circadian ‘clock’). The alternation of environmental light and darkness synchronizes (entrains) these rhythms to the natural day–night cycle, and underlying mechanisms have been investigated using singly housed animals in the laboratory. But, most species ordinarily would not live out their lives in such seclusion; in their natural habitats, they interact with other individuals, and some live in colonies with highly developed social structures requiring temporal synchronization. Social cues may thus be critical to the adaptive function of the circadian system, but elucidating their role and the responsible mechanisms has proven elusive. Here, we highlight three model systems that are now being applied to understanding the biology of socially synchronized circadian oscillators: the fruitfly, with its powerful array of molecular genetic tools; the honeybee, with its complex natural society and clear division of labour; and, at a different level of biological organization, the rodent suprachiasmatic nucleus, site of the brain's circadian clock, with its network of mutually coupled single-cell oscillators. Analyses at the ‘group’ level of circadian organization will likely generate a more complex, but ultimately more comprehensive, view of clocks and rhythms and their contribution to fitness in nature.
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Nohales, Maria A. « Spatial Organization and Coordination of the Plant Circadian System ». Genes 12, no 3 (20 mars 2021) : 442. http://dx.doi.org/10.3390/genes12030442.
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The plant circadian clock has a pervasive influence on many aspects of plant biology and is proposed to function as a developmental manager. To do so, the circadian oscillator needs to be able to integrate a multiplicity of environmental signals and coordinate an extensive and diverse repertoire of endogenous rhythms accordingly. Recent studies on tissue-specific characteristics and spatial structure of the plant circadian clock suggest that such plasticity may be achieved through the function of distinct oscillators, which sense the environment locally and are then coordinated across the plant through both intercellular coupling and long-distance communication. This review summarizes the current knowledge on tissue-specific features of the clock in plants and their spatial organization and synchronization at the organismal level.
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Mikaberidze, Guram, et Raissa M. D’Souza. « Sandpile cascades on oscillator networks : The BTW model meets Kuramoto ». Chaos : An Interdisciplinary Journal of Nonlinear Science 32, no 5 (mai 2022) : 053121. http://dx.doi.org/10.1063/5.0095094.
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Cascading failures abound in complex systems and the Bak–Tang–Weisenfeld (BTW) sandpile model provides a theoretical underpinning for their analysis. Yet, it does not account for the possibility of nodes having oscillatory dynamics, such as in power grids and brain networks. Here, we consider a network of Kuramoto oscillators upon which the BTW model is unfolding, enabling us to study how the feedback between the oscillatory and cascading dynamics can lead to new emergent behaviors. We assume that the more out-of-sync a node is with its neighbors, the more vulnerable it is and lower its load-carrying capacity accordingly. Also, when a node topples and sheds load, its oscillatory phase is reset at random. This leads to novel cyclic behavior at an emergent, long timescale. The system spends the bulk of its time in a synchronized state where load builds up with minimal cascades. Yet, eventually, the system reaches a tipping point where a large cascade triggers a “cascade of larger cascades,” which can be classified as a dragon king event. The system then undergoes a short transient back to the synchronous, buildup phase. The coupling between capacity and synchronization gives rise to endogenous cascade seeds in addition to the standard exogenous ones, and we show their respective roles. We establish the phenomena from numerical studies and develop the accompanying mean-field theory to locate the tipping point, calculate the load in the system, determine the frequency of the long-time oscillations, and find the distribution of cascade sizes during the buildup phase.
Thèses sur le sujet "Endogenous oscillators"
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Zankoc, Clément. « The role of external and endogenous noise in neural network dynamics and statistics ». Doctoral thesis, 2019. http://hdl.handle.net/2158/1154326.
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Noise is ubiquitous, stemming from the surrounding environment or arising from the inherent stochasticity of the system under consideration. Its presence may qualitatively change the behavior of a physical system, possibly leading to surprising and unexpected phenomena, and, as such, it should be accommodated for in realistic models. In this work, I present several models, that bear interest in neuroscience, in which noise plays a role of paramount importance. Throughout my thesis, investigations are conducted by means of both analytical and computational methods. First, I introduce, and further develop key analytical tools for tackling analytically the dynamics of a stochastic system. More specifically, I develop a perturbative technique which allows for computing the statistics of such systems even if they do not obey a gradient dynamics. Second, I focus on purely stochastic oscillators. I show that a collection of such oscillators, occupying the nodes of a generic network, can organize at the macroscopic level yielding noise-sustained spatiotemporal pattern with long-range correlations. Then, the same oscillators are organized in a directed unidirectional lattice with adjacent connections. The endogenous component of noise, coupled to a certain topology of the embedding space, seeds a coherent amplification of the signal across the lattice. Almost periodic oscillations emerge that I thoroughly investigate. Finally, I demonstrate that the coherent amplification of an imposed noisy perturbation destabilizes the synchronous state of an ensemble made of deterministic oscillators also when a conventional linear stability analysis would deem the system resilient to small external disturbances.
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Ciofini, Alice. « Interaction among celestial orienting factors and their functioning in supralittoral crustaceans ». Doctoral thesis, 2018. http://hdl.handle.net/2158/1120833.
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Behavioural investigations conducted since the Fifties have revealed that the amphipod Talitrus saltator can rely on both the sun and the moon as compass cues in its zonal recovery; recently, evidence for discrete endogenous oscillators underlying its time-compensated solar and lunar orientation has been also given. T. saltator is the first species shown able to obtain compass information by using only the skylight intensity gradient. Instead, it does not rely on the celestial polarization pattern despite its sensitivity to polarized light. Although discrete receptors detecting UV-blue and green light have been identified within its compound eye, neither the capability of this species to use the spectral pattern of the sky nor the regionalisation of its visual pigments (eventually indicating the existence of a DRA) has been investigated. Furthermore, investigations on the structure of its compound eye conducted so far are quite scarce despite the importance of the vision in the perception of orienting stimuli. Evidence for solar and lunar orientation has been provided also in the isopod Tylos europaeus. However, as opposed to its ability to orientate to the sun, its moon compass-based orientation has not been confirmed. The aims of this work are: 1) to deepen our knowledges on the use of the celestial gradients by T. saltator, 2) to evaluate the regionalization of its visual capabilities, 3) to assess the optical and functional structure of its compound eye, 4) to investigate the anatomical localisation of the time-keepers regulating the sun and the moon compass mechanisms, 5) to assess the existence of antennal time-keepers involved in celestial orientation and 6) to confirm the capability of T. europaeus to orientate to the moon. In this work, the first evidence for the use of the celestial spectral gradient as a compass cue by T. saltator was obtained. The skylight intensity profile has also been confirmed to constitute a reliable orienting reference and it has been shown that it exists a minimum threshold of the gradient effectively recognised and used. Instead, tests carried out did not point out a clear spatial distribution of the photoreceptors within the eye of this species. However, it has been revealed that the dorsal edge of the eye plays an important role in the perception of celestial factors. These results, along with evidence of straight ommatidia occurring in this area of the eye, suggest a regionalisation of the visual capabilities in T. saltator and are in agreement with the existence of a DRA. Furthermore, it was shown that this species mainly possesses hook-shaped ommatidia (except for the dorsal region of its eye) and it was suggested that their photoreception efficiency was enhanced by reflecting pigment cells localized between them. Moreover, it was found that the oscillators underlying the sun and the moon compass mechanisms are localised in separate localities. In fact, the antennae seem to be the anatomical site of the time-keepers responsible for the lunar orientation (although our results suggest that timing inputs from these oscillators are downstream integrated), whereas those involved in solar orientation are located elsewhere (probably in the brain). Intriguingly, present work provided first molecular evidence for time-keepers in T. saltator by revealing rhythmicity in the expression of core genes in both brain and antennae (thus supporting the existence of oscillators in these appendages). Finally, it has been fully confirmed the capability of T. europaeus to orientate under the moon and provided partial evidence for discrete time-keepers underlying the functioning of the sun and the moon compass systems in this species.
Livres sur le sujet "Endogenous oscillators"
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Lockley, Steven W. Principles of sleep–wake regulation. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198778240.003.0002.
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The 24-hour sleep–wake cycle is generated by two oscillatory processes: an endogenous hypothalamic circadian pacemaker and a sleep- and wake-dependent homeostat. These processes combine to maintain a consolidated bout of sleep at night and relatively stable waking function across the day. They also combine to determine ‘diurnal preference’—whether one is a ‘lark’ or an ‘owl’—a reflection of the phase relationship between the circadian and homeostatic processes. These processes are affected directly by light, either through resetting of the circadian pacemaker or its direct alerting effects. Sleep deficiency and circadian disruption have been associated with a higher risk of chronic disease, although the methodology for assessing these exposures is not optimal. Both sleep and the circadian system also have myriad influences on other aspects of our physiology, behaviour, and metabolism; therefore, steps should be taken to reduce their potential confounding effects in epidemiological studies.
Chapitres de livres sur le sujet "Endogenous oscillators"
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Colella, Cristianna. « Endogenous Oscillations ». Dans Encyclopedia of Animal Cognition and Behavior, 2337–38. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-319-55065-7_1920.
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Colella, Cristianna. « Endogenous Oscillations ». Dans Encyclopedia of Animal Cognition and Behavior, 1–3. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-319-47829-6_1920-1.
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Chay, Teresa Ree, et Hong Seok Kang. « Multiple Oscillatory States and Chaos in the Endogenous Activity of Excitable Cells : Pancreatic β-Cell as an Example ». Dans Chaos in Biological Systems, 173–81. Boston, MA : Springer US, 1987. http://dx.doi.org/10.1007/978-1-4757-9631-5_20.
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Riess Jones, Mari. « The Tunable Brain ». Dans Time Will Tell, 34–57. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780190618216.003.0003.
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This chapter introduces some elementary entrainment concepts such as phase space, phase portrait, bifurcation, and attractors. Limit cycle oscillations are introduced. It also provides a simplified overview of cortical activities in the human brain. It introduces concepts related to the synchrony between a pair of oscillations (endogenous entrainment), including examples of mode-locking synchronicities. Furthermore, it discusses the possibility of synchronous activities among whole configurations of cortical oscillations. The main aim of this chapter is to show the potential of brain oscillations to entrain to one another in various ways (modes of synchrony). Hence, a variety of forms of endogenous entrainment are discussed. Finally, the concept of attractors as abstract states of synchrony to which neighboring nonsynchronous states are drawn is introduced.
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Riess Jones, Mari. « Tuning in to Very Fast Events ». Dans Time Will Tell, 107–34. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780190618216.003.0006.
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This chapter demonstrates that entrainment applies to very fast events, namely sounds with high frequencies. To illustrate this, prominent approaches to pitch perception are sketched along with basic pitch perception phenomena (e.g., virtual pitch perception). In this chapter, multiple frequency components comprise a single complex sound, and people must judge the pitch of this collection of frequencies. Both a successful psychoacoustic theory of pitch perception and a dynamic attending approach offer valid explanations of various phenomena surrounding the pitch of such sounds. This suggests the potential of entrainment in describing pitch perception (i.e., entrainments at fast time scales). The perception of consonance and dissonance is also considered, where dissonance is linked to complex synchronicities termed attractors. Finally, this chapter introduces oscillator clusters, a group of endogenously entrained oscillations.
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« Modelling the endogenous oscillations and predictions from timeseries analysis ». Dans Human Demography and Disease, 75–86. Cambridge University Press, 1998. http://dx.doi.org/10.1017/cbo9780511600487.007.
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Joyce, Daniel S., et Jamie M. Zeitzer. « Circadian Rhythms ». Dans Management of Sleep Disorders in Psychiatry, sous la direction de Amit Chopra, Piyush Das et Karl Doghramji, 41–53. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780190929671.003.0004.
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Circadian rhythms are endogenous, near 24-hour oscillations that underlie nearly all facets of our health and behavior. The daily cycle of sleep and wake is the most conspicuous circadian-influenced behavior in humans. This chapter introduces the circadian rhythms in humans that give rise to our daily cycling of sleep and alertness, including their fundamental features and loci of origin. The interplay between circadian rhythms and sleep is discussed, including physiological and behavioral methods for the measurement of circadian rhythms. Finally, typical and atypical features of circadian rhythms in relation to health and aging are considered with particular reference to the impact of modern societal pressures.
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Pritchett, David, Angus S. Fisk, Russell G. Foster et Stuart N. Peirson. « Basic mechanisms of, and possible treatment targets for, sleep–wake disorders ». Dans New Oxford Textbook of Psychiatry, sous la direction de John R. Geddes, Nancy C. Andreasen et Guy M. Goodwin, 1115–23. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198713005.003.0109.
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Circadian rhythms are endogenous 24-hour oscillations in physiology and behaviour that enable organisms to predict and adapt to the rhythmic changes of the day/night cycle. While the rhythm of activity and rest is perhaps the most familiar, changes in body temperature, heart rate, hormone production, and even cognitive function also occur. By contrast, the daily pattern of sleep and wake is not solely determined by the circadian system and is also regulated by a homeostatic process that increases with prolonged waking. Sleep and circadian rhythm disruption (SCRD) is commonly observed in psychiatric disorders, such as schizophrenia, although it is unclear as to the basis of this comorbidity. The chapter provides an overview of the links between SCRD and schizophrenia, highlighting the potential sources of this association. Moreover, the chapter describes how targeted treatment of the underlying sleep and circadian disruption in this patient group may provide a novel therapeutic avenue to ameliorate their primary symptoms.
Actes de conférences sur le sujet "Endogenous oscillators"
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Blanch, Ian G., Duane W. Storti, Rhonda L. Anderson, Mark A. Ganter et Per G. Reinhall. « Novel Autonomous Underwater Vehicle Based Upon Jellyfish Locomotion ». Dans ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/detc2007-34440.
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This paper describes the process of developing a novel biomimetic autonomous underwater vehicle (AUV) inspired by jellyfish locomotion. Our interest in an AUV that mimics jellyfish locomotion stems from the jellyfish’s simplistic and robust physiology and neurological makeup. Jellyfish swimming gates are controlled by a neural architecture consisting of an outer nerve ring and an inner nerve ring. The inner nerve ring is responsible for incorporating the sensory input from the outer ring and innervating the subumbrellar swimming muscles. Additionally, cells in the inner ring generate endogenous rhythms and act as pacemakers. The system of pacemakers generates the highly maneuverable swimming gates that can be observed in jellyfish; swimming vertically, turning and hovering. The swimming gates have been shown to correspond to the dynamics of the response of a system of coupled identical van der Pol oscillators. These oscillators are capable of creating in-phase, out-of-phase and “asymmetric” phase-locked dynamics that are plausibly related to the basic modes of jellyfish locomotion of coordinated bout swimming, hovering, and turning, respectively. In addition, the system of oscillators is fault tolerant; if the modeled system of oscillators is disrupted, analogous to sections of the jellyfish being damaged, the oscillators adjust and maintain effective swimming gates allowing the jellyfish to remain mobile. The simplicity and fault tolerance of the oscillatory system makes it an ideal model for a locomotion control system for an AUV. The objective of the Jellyfish AUV project is to emulate the locomotion and control mechanisms of the biological jellyfish to create a simple and robust AUV, which is both highly maneuverable and low in cost. The iterative design process that resulted in a working Jellyfish AUV is detailed in this paper. Numerous designs were created, exploring different combinations of actuator mechanisms, body types and control systems. Different actuators were evaluated for their ability to meet our design requirements. These actuators ranged from off the shelf servos to the more exotic shape memory alloys (SMAs) and ionic polymer metal composites (IPMCs.) By the completion of the prototyping phase of the Jellyfish AUV project we had created a low cost AUV using off the shelf components including, servos, linkages and a microprocessor based control system. The input to the servos was derived from a system of coupled oscillators which were tuned to mimic the observation jellyfish gates. In addition, using the Jellyfish AUV prototype, we showed that the identified servo input patterns roughly translate to swimming, hovering, and turning.
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Barnes, Anna, Garry Honey, Alle-Meije Wink, Edward T. Bullmore et John Suckling. « Modulation of the fractal properties of low frequency endogenous brain oscillations in functional MRI by a working memory task. » Dans 2008 IEEE International Joint Conference on Neural Networks (IJCNN 2008 - Hong Kong). IEEE, 2008. http://dx.doi.org/10.1109/ijcnn.2008.4634338.
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